I personally think the focus is wrong.
I think what count most is what you do with the life you are in now....what goals one put up....how we fulfill them and so on.
By focus on how many life we need, we take away focus from what is important, which is now, and it can also be used as a "sleeping pillow" or excuse that we can't achieve thing because we need more life.
Reincarnation, together with much else, is beliefs, and not fact.
If the belief is something that benefit you in this life, then the belief is good.
If the belief is something that prevent you from living to the full in this life, then the "belief is wrong"....again in my opinion or belief
If you believe that "old soul" gives you greater benefit in this life...well then we are all "old souls", and none can prove different.....we are all descendant of the first life on earth...and we all carry all our ancestors genes
